Lise Meitner’s Genius

In response to:

In his review of a biography of Leo Szilard [NYR, October 7, 1993], M.F. Perutz repeats the old canard that, “…Otto Hahn and Fritz Strassmann discovered the fission of uranium by neutrons.” The discovery of nuclear fission was made by Prof. Lisë Meitner. Although Hahn and Strassmann got her Nobel prize, crediting them with Meitner’s discovery is like giving credit for a great chef’s recipe to the kitchen helper who stirred the pot. For the fascinating story of how a Jewish woman managed to enter a university, study physics, become one of the select few who understood Einstein’s theories, survive the Holocaust, and make the single discovery which ultimately gave the Allies a decisive victory in WWII, I refer the reader to: Lisë Meitner: Atomic Pioneer, Crown Publishers, 1969; Otto Hahn: A Scientific Autobiography, Charles Scribners Sons, 1966; and various writings of Albert Einstein who, when called, “the father of the bomb,” responded that the bomb had no father but it had a mother, Lisë Meitner. Otto Hahn had no mathematical background and would have been an ordinary paint chemist except for the fact that Meitner was female and women were not permitted to work in university laboratories. The two teamed up with Hahn pretending to be the scientist and Meitner the helper to gain lab access. Throughout their careers it was Meitner who designed and oversaw the experiments intended to test her theories, and while Hahn was capable of carrying them out and reporting the results, only Meitner could interpret them correctly. Like Szilard, Meitner was concerned with the consequences of her discovery and spent the post-war years seeking ways to control and safely use nuclear fission. Unfortunately, funding was difficult to find as most governments were seeking more devastating weapons like the hydrogen bomb and inter-continental missiles. Genius is rare and a terrible thing to waste. If we are to avoid discarding scientists on the basis of sex, creed, ethnicity, orientation, or other irrelevancies, it is important that we ascribe credit, or blame as the case may be, where it is due.

Mark E. Smith
San Diego, California

M.F Perutz replies:

I am glad that Mr. Smith has drawn your readers’ attention to Lise Meitner’s crucial role in the discovery of nuclear fission, but he is wrong to reduce Hahn’s to that of a kitchen helper. Lise Meitner was born in Vienna in 1878 and received her doctorate in physics from Vienna University in 1906. Next year, she moved to Berlin and began her thirty-year-long collaboration with the chemist Otto Hahn. Emil Fischer, the head of the university chemical laboratory, tolerated no women in his laboratory, but he agreed reluctantly to give Meitner and Hahn a place in what used to be the wood workshop in the basement. In the 1930s, the time Mr. Smith has in mind, she was head of the physics department of the Kaiser Wilhelm Institute for Chemistry of which Hahn was director and, until 1934, she was also a professor at Berlin University.
In 1935 Meitner persuaded Hahn to join her in a study of an effect recently discovered by Enrico Fermi in Rome: new radio-activities induced in uranium by irradiation with neutrons. Fermi had attributed these to the creation, by neutron capture, of elements heavier than uranium, the heaviest element then known, but he had not identified these new elements chemically. Meitner believed that Hahn’s uniquely sensitive methods might be capable of doing so.

Their collaboration was brought to an end by Hitler’s annexation of Austria in March 1938. Before that, her Austrian nationality had protected her from persecution as a Jew, but now she was in danger. Peter Debye, the Dutchman who headed the Kaiser Wilhelm Institute for Physics, arranged her flight into Holland from where she went on to Stockholm.

On December 19, 1938, Hahn wrote to her that he and Strassmann had found it impossible to separate one of the radioactive elements produced by the irradiation of uranium with neutrons from barium, an element of only slightly more than half the weight of uranium. He suggested to her that perhaps she could put forward some imaginative explanation.

When Meitner’s young physicist nephew Otto Robert Frisch came to visit her in Sweden over Christmas, they realized that barium could have been formed only if absorption of a neutron had induced the uranium nucleus to split in half, and they predicted the large amount of energy that would have been released in the process. They published their interpretation in the English journal Nature in February 1939, only two days after Hahn and Strassmann’s discovery had appeared in its German counterpart, the Naturwissenschaften. In two later papers, one by Frisch alone and the other by Meitner and Frisch, they verified the predicted energy experimentally.

Hahn was no ordinary paint chemist, but one of the world’s leading radiochemists. After the war Meitner stressed in an interview on German television that Hahn had been the only person in the world with chemical methods sufficiently refined to separate the infinitesimally small quantities of new radioactive elements produced by the irradiation of uranium with neutrons from the bulk of the uranium itself, as well as from the accompanying, naturally present radium and its radioactive decay products.

It was a remarkable feat, for which Hahn deserved the Nobel Prize, but I thought that the Nobel Committee for Chemistry had been narrow-minded in not awarding it jointly to him and his physicist colleague Meitner. In 1964, the US Atomic Energy Commission invited me to nominate a candidate for the prestigious Enrico Fermi Prize. I nominated Lise Meitner who was by then living in Cambridge. When the news of her prize arrived she was eighty-seven and too frail to travel to Washington to receive it. Instead, the physicist and Nobel laureate Glen Seaborg traveled to Cambridge, and on October 23, 1966, presented the prize to her on behalf of the Atomic Energy Commission at my wife’s and my home. Lise Meitner died in 1968, three months after her lifelong friend and colleague Otto Hahn.